1. Field of the Invention
This invention relates to an image forming device, and more particularly a temperature control for a fixing unit in an image forming device having a thermal fixing system.
2. Prior Art
The aforesaid image forming device has a fixing roller storing a heater therein, for example, and the fixing roller is heated by the aforesaid heater and then the toner on the recording sheet is fixed on the recording sheet. However, in the event that the image forming device is not used for a long period of time, the heating operation for the aforesaid fixing roller may cause an electrical power consumption to be increased, resulting in that its running cost is increased.
In view of this fact, there is proposed a method for turning off an electrical energization for the fixing roller so as to save an electrical power in the event that the image forming device is not used for a long period of time.
However, the aforesaid method has had some problems in that the temperature of another element, for example, a light sensing drum or the like in the image forming device having a set temperature accommodating range is remarkably reduced if the surrounding air temperature is excessively decreased, resulting in that an operation of the image forming device becomes unstable and the image quality is deteriorated.
In view of the foregoing, the present invention has been invented, and it is an object of the present invention to provide an image forming device which can prevent an image quality from being deteriorated while saving a consumption power.